I want to build a 1200w grid tie solar system that I can plug into the side of my home.

[cs1234]

I have my electric bill that gives hourly, daily and yearly summaries. I imagine this data would probably be sufficient if you wanted it. If you need daily's let me know.

For determining your minimum load at any time, you need by the minute or by the second data. Do you have anything you always run, 24/7? Like some air filters or crypto miners?

 

[rebellyellsolar]

large freezer, fridge freezer combo, mini fridge. Those are the only things on all the time, think they kick on and off, though.

 

[cs1234]

large freezer, fridge freezer combo, mini fridge. Those are the only things on all the time, think they kick on and off, though.

That probably won't work as a base load. I'm not sure you will be able to use a GTIL without getting into trouble.

Your best bet is to go the route of a small AIO 2-3kw inverter with some batteries. Run the AC unit off that directly, and it will use the power from solar/batteries first.. then the AC power.

Instead of piecing together one of your own, something like an Ecoflow Delta 2 would possibly work well for you. It could probably start an inverter window ac unit.

 

[rebellyellsolar]

UHGHGT it hurts. That things very expensive. Got any recommendations for piecmailing one together that doesn't sting as much? I really do appreciate the help btw. I have no idea how to do what I want to do and all of you are very kind and patient with me which if I'm being honest, I was expecting to get roasted into ash for even asking. I think you're right though, there wouldn't be any waste, I wouldn't just be throwing solar at a ac unit, I would be making a proper system, I just man that things too pricey for me.

 

[cs1234]

UHGHGT it hurts. That things very expensive. Got any recommendations for piecmailing one together that doesn't sting as much? I really do appreciate the help btw. I have no idea how to do what I want to do and all of you are very kind and patient with me which if I'm being honest, I was expecting to get roasted into ash for even asking.

It's on sale for $679 right now on Amazon. That's a pretty good price for something large enough to run pretty much anything plugged into a 120v 15amp outlet.

 

[rebellyellsolar]

It's on sale for $679 right now on Amazon. That's a pretty good price for something large enough to run pretty much anything plugged into a 120v 15amp outlet.

Okay, it is what it is, I'll just save up, got almost a year before I need more ac so plenty of time, I guess. Thanks you again for your help.

 

[cs1234]

Okay, it is what it is, I'll just save up, got almost a year before I need more ac so plenty of time, I guess. Thanks you again for your help.

You could always try the GTIL with the ac unit and just panels. The GTIL is unlikely to harm anybody, but the power company might tell you to remove it or they are going to shut your power off.

 

[rebellyellsolar]

You could always try the GTIL with the ac unit and just panels. The GTIL is unlikely to harm anybody, but the power company might tell you to remove it or they are going to shut your power off.

No, you don't know this but I was always going to end up doing what you specifically recommended, I know how to listen to people who know what they are talking about and will happily tear up my own designs to adopt theirs. I'll get one of these ecoflows. PLus the conversation took three days to come full circle and I now understand the WHY in why I shouldn't grid tie, which is what was most important to me.

 

[cs1234]

No, you don't know this but I was always going to end up doing what you specifically recommended, I know how to listen to people who know what they are talking about and will happily tear up my own designs to adopt theirs. I'll get one of these ecoflows. PLus the conversation took three days to come full circle and I now understand the WHY in why I shouldn't grid tie, which is what was most important to me.

It doesn't have to be the ecoflow. You just want an inverter with batteries. Keep your eyes out for deals, read some more of the forum. Watch Will Prowse, Hobotech, Jasonoid and others on youtube if you prefer videos over combing forums.

 

[rebellyellsolar]

It doesn't have to be the ecoflow. You just want an inverter with batteries. Keep your eyes out for deals, read some more of the forum. Watch Will Prowse, Hobotech, Jasonoid and others on youtube if you prefer videos over combing forums.

Something sub 500 bucks would be nice, but so is everything about the ecoflow. If you have any cheaper but similar suggestions, I'll have them, otherwise thats now the plan.

 

[cs1234]

You might be able to get away with something smaller. It's really going to depend on what the actual inrush power draw and running power draw is on the ac unit you want to use. Once you determine that, you can hunt for your inverter.

 

[rebellyellsolar]

You might be able to get away with something smaller. It's really going to depend on what the actual inrush power draw and running power draw is on the ac unit you want to use. Once you determine that, you can hunt for your inverter.

hey quick question, the inverter you linked only accepts 500 watts of solar, thats half of what I need from solar, any ideas on how I could use more or is it like a , figure it kind of deal.

 

[rebellyellsolar]

This picture was helpful to me in understanding. This way makes more sense, even if it's more expensive. best not let my ambition for a cheap way out cheat me out of a much better experience. If I can get ten years out of the battery and system, it can still be done for less than a grand it looks like. Well, maybe 1500. Could someone help me design a small cheap system?

 

[OM617YOTA]

What would you do?

Originally you said you wanted to shave enough power usage off to get below the next electrical bill tier increase.

First of all, how much are you over the limit are you? How much do you need to shave off? How much are you saving by getting below that limit? If you're going to spend a thousand bucks on solar stuff to save $50/mo, and only during AC season, you may never get a return on investment by buying solar equipment. Having solid data will also tell you how much power you need to generate or save to make this whole endeavor worth doing at all.

You're limited in what you can do by being in a rental, but if I was in your situation, I'd look long and hard at reducing my existing usage before I looked at generating anything. As the old saying goes, it's easier to save a watt than generate a watt.

Here are a pile of ideas, no particular order, just as they came to mind. Most of this is pretty old school:

Do you have blackout curtains? There are insulated curtains, and also window films which can reduce solar infiltration - same idea as tinted windows on your car.

Turn off the dang lights and TV when no one is in the room. Even with LED bulbs, if leaving them on costs you $2/mo, and you normally wouldn't care about the $2, if getting under that billing tier is the main goal, then this all adds up. Some TVs burn a surprising amount of power, even if they're flat screen.

Turn off your computer and your 12 monitors when you're not using it.

Put as many wall warts and chargers as you can on power strips, and turn them all off when not in use.

Do your doors have good seals around them? A $30 IR thermometer can help you find air leaks. Fixed with as simple as a rolled up towel on the floor, or as proper as installing a new threshold and weather stripping.

If you cook with an old school resistance electric cooktop, look at an induction plug-in hot plate and use that as much as you can. As well as being more efficient itself, it'll also reduce the load on your AC system, saving more power. Force multiplier.

If you boil a lot of water, drink a lot of tea or something, look at a self contained electric kettle vs. boiling water on the stove. Much more efficient than a stovetop burner, also cuts load on the AC system. If you are boiling a kettle on the stove, cool it down with cold water when you're done, so that heat isn't radiating into the house, making the AC work harder.

Can you use the super efficient window AC you're talking about, and only AC the room or rooms you're occupying? My parents used to heat the living room with a wood stove, and hung a sheet between the living room and the rest of the house to keep the heat in the room we were occupying. Same idea could apply here.

Cook outside during AC season. If you're simmering a stew, put it in a crockpot on your back porch. Don't dump all that heat into your house, where your AC then has to work to pull it out of the house. Same thing with sous vide. Use your induction hot plate and take it outside. I do this when frying fish or making curry anyway, otherwise the house smells like curry for a week afterwards. Dump your hot sous vide water and cool the container down with cool water, don't let all the heat radiate into the house for the AC to then remove.

Use the old-school pre-AC cooling method when you can, open up your house at night and run fans to vent the heat. Close it up in the morning, before the heat of the day. No clue where you live, if it's still 90F at midnight this obviously won't be an option.

Talk to your landlord, they might be onboard with you making other changes as well. Water heater blanket, extra attic insulation, timer on the water heater, etc.

Get the data first, though.

 

[rebellyellsolar]

Originally you said you wanted to shave enough power usage off to get below the next electrical bill tier increase.

First of all, how much are you over the limit are you? How much do you need to shave off? How much are you saving by getting below that limit? If you're going to spend a thousand bucks on solar stuff to save $50/mo, and only during AC season, you may never get a return on investment by buying solar equipment. Having solid data will also tell you how much power you need to generate or save to make this whole endeavor worth doing at all.

You're limited in what you can do by being in a rental, but if I was in your situation, I'd look long and hard at reducing my existing usage before I looked at generating anything. As the old saying goes, it's easier to save a watt than generate a watt.

Here are a pile of ideas, no particular order, just as they came to mind. Most of this is pretty old school:

Do you have blackout curtains? There are insulated curtains, and also window films which can reduce solar infiltration - same idea as tinted windows on your car.

Turn off the dang lights and TV when no one is in the room. Even with LED bulbs, if leaving them on costs you $2/mo, and you normally wouldn't care about the $2, if getting under that billing tier is the main goal, then this all adds up. Some TVs burn a surprising amount of power, even if they're flat screen.

Turn off your computer and your 12 monitors when you're not using it.

Put as many wall warts and chargers as you can on power strips, and turn them all off when not in use.

Do your doors have good seals around them? A $30 IR thermometer can help you find air leaks. Fixed with as simple as a rolled up towel on the floor, or as proper as installing a new threshold and weather stripping.

If you cook with an old school resistance electric cooktop, look at an induction plug-in hot plate and use that as much as you can. As well as being more efficient itself, it'll also reduce the load on your AC system, saving more power. Force multiplier.

If you boil a lot of water, drink a lot of tea or something, look at a self contained electric kettle vs. boiling water on the stove. Much more efficient than a stovetop burner, also cuts load on the AC system. If you are boiling a kettle on the stove, cool it down with cold water when you're done, so that heat isn't radiating into the house, making the AC work harder.

Can you use the super efficient window AC you're talking about, and only AC the room or rooms you're occupying? My parents used to heat the living room with a wood stove, and hung a sheet between the living room and the rest of the house to keep the heat in the room we were occupying. Same idea could apply here.

Cook outside during AC season. If you're simmering a stew, put it in a crockpot on your back porch. Don't dump all that heat into your house, where your AC then has to work to pull it out of the house. Same thing with sous vide. Use your induction hot plate and take it outside. I do this when frying fish or making curry anyway, otherwise the house smells like curry for a week afterwards. Dump your hot sous vide water and cool the container down with cool water, don't let all the heat radiate into the house for the AC to then remove.

Use the old-school pre-AC cooling method when you can, open up your house at night and run fans to vent the heat. Close it up in the morning, before the heat of the day. No clue where you live, if it's still 90F at midnight this obviously won't be an option.

Talk to your landlord, they might be onboard with you making other changes as well. Water heater blanket, extra attic insulation, timer on the water heater, etc.

Get the data first, though.

Yea, and for the most part that's pretty much what I want to do. I'm getting a lot of constructive help and advice and I did take the time to read everything you wrote. I'm just getting my bearings here and trying to figure out what makes the most sense as you say. Your suggestions to help save on efficiency are good, and I will look into them. I'm not going super over, thee problem is I'm already uncomfortable during the day at my cost saving ac usage (82 day / 78 night F with ac) and it's not getting better. I think the first move is to make cuts, and increase efficiency which is already pretty bare bones. Then it's to watch the electricity for a while while filling in insulation gaps as you say, if the land lord pays for it. I know one room basically has none and I've not investigated why (lazy cunt). So that will be on the agenda now. However, I find myself in a bit of a nexus of ideas outside of that. I know I need to figure out EXACTLY what energy I go over, how much I need to avoid that, and what that means cost wise. I can do that now... My bill for July, my hottest month shows 106.49 for the first 1000kwh @ 5.2c a kWh and 39.27more for 345 kWh at a rate of 5.973c/kWh. For a total of 145.76 @ 1345kWh. There is a third tier, I have not touched it. It's 6.9c/kWh so I do want to avoid it at all cost and the threshold is 1500kWh. If I were to use the delta 2 679 and 2x used 370w 41v constant 11.42 amp panels that would cost 120 each (240 total) I would have spent 919, round to 1100 for parts. This is my delima could do a jank system for decreasing yield / value / quality / cost the aforementioned system being the second most expensive I have considered. Next least expensive in order would be a diy system, which I could use two panels with to charge an inverter 3kva hybrid dc 24v to 110v (still limited to too panels due to volt/watt limit parallel would be required. I could do the inverter and battery for 516 + 240 in panels. + money for lines breakers etc back at the magic 1000 bucks. And that system has only a marginal improvement over the all in one as far as wattage goes its really worse but I have no idea how to design a hybrid system for less than a thousand bucks I could use in concert with the ac so I'm winging it. Then there are various grid tie solutions, which are messy and dangerous, but cheaper. Which is why they were my focus. If you have any advice I'm a bit lost and could use it.

 

[OM617YOTA]

For a total of 145.76 @ 1345kWh.

I'm seriously not trying to rain on your parade here, but if your bill for your hottest month is $145.76(assuming you're in the USA), and you're only trying to trim that peak off, and only during AC season, then solar may never offer you an ROI. Even if you shave the $40 at the second tier level, you're still looking at 25 months of savings just to break even on a $1k investment. Depending on how long your AC season is, that could be a lot of years. With those numbers, and cost saving as the main goal, I would simply dustbin the whole adventure right there. Reduce usage where reasonable and just pay for grid power.

Look at other ways to generate ROI with your $1k. If you have any debt, especially high interest CC debt, you might save more on interest by dumping $1k into that than you'd save by building a $1k solar power system.

If your goal is to learn and have an interesting new hobby, that's an entirely different matter. Welcome to the club, and game on.

 

[rebellyellsolar]

I'm seriously not trying to rain on your parade here, but if your bill for your hottest month is $145.76(assuming you're in the USA), and you're only trying to trim that peak off, and only during AC season, then solar may never offer you an ROI. Even if you shave the $40 at the second tier level, you're still looking at 25 months of savings just to break even on a $1k investment. Depending on how long your AC season is, that could be a lot of years. With those numbers, and cost saving as the main goal, I would simply dustbin the whole adventure right there. Reduce usage where reasonable and just pay for grid power.

Look at other ways to generate ROI with your $1k. If you have any debt, especially high interest CC debt, you might save more on interest by dumping $1k into that than you'd save by building a $1k solar power system.

If your goal is to learn and have an interesting new hobby, that's an entirely different matter.

That's sort of why I was looking at grid tie, panel to inverter, inverter power out, do that with a power strip and were at sub 500 bucks tie the sense to the ac itself and run something else on the strip to have a lesser risk of that back-feed bouncing back on the grid. The issue with that is while the cost in money is low, the cost in danger is high, overload, surge, and execution require skills and other things I don't have. But the whole system can be had for less than the thing cs mentioned. Panels all of it, and I would be without a battery. Which kind of kicked off my orbit into the nexus of choices. Raw solar, to ac unit in window, simple cheapish would do more or less what I want but that risk makes me pause. I do not want to hurt anyone, or burn down this house, those things are an unacceptable risk to me. There seems to bee a happy medium combination of hybrid inverter/battery/panels but god damn if I couldn't figure out how to do it the hybrid safer way for less than a grand. Maybe I should juts forget it, some things aren't feasible.

 

[OM617YOTA]

I definitely wouldn't do stealth grid tie or back feed at all, wouldn't interface with the existing house wiring at all. Risk vs. reward ratio just isn't there.

For the numbers you're looking at, absolute lowest cost is going to be paramount to break even. There are 3kw 24v all in one inverters on Amazon for $226 which would run a window AC. Wrecking yards around here used to sell used car batteries for $20, you might have something similar in your area. A couple used batteries in series would get you to 24v. Set your voltage limits so the batteries stay charged all the time so they don't die in less than a week; the batteries would only be a buffer, and you'd be running the system only while the sun is shining. Closest/cheapest option I can think of for a stand alone "battery less" option.

I'd still really look at savings in other areas first.

 

[rebellyellsolar]

I definitely wouldn't do stealth grid tie or back feed at all, wouldn't interface with the existing house wiring at all. Risk vs. reward ratio just isn't there.

For the numbers you're looking at, absolute lowest cost is going to be paramount to break even. There are 3kw 24v all in one inverters on Amazon for $226 which would run a window AC. Wrecking yards around here used to sell used car batteries for $20, you might have something similar in your area. A couple used batteries in series would get you to 24v. Set your voltage limits so the batteries stay charged all the time so they don't die in less than a week; the batteries would only be a buffer, and you'd be running the system only while the sun is shining. Closest/cheapest option I can think of for a stand alone "battery less" option.

I'd still really look at savings in other areas first.

Yea thats what I'm looking at now, thank you for the help and caution.

 

[rebellyellsolar]

Also, I thank you for your help. Do you see a minimalist system I could design that makes any sense? Or is it more just "you're bill isint bad your ac is cheap suck it up" not that you would say something so crass, It's just the truth of the matter, I think. However, IF theres a small ish system like you said, that makes sense, then I could do that after I get the new ac and maybe insulate some more, if it still makes sense.